\documentclass[12pt]{article}
\begin{document} \large
\begin{eqnarray*}
E_T & = & \sum_i [ E_i^{self} (q_i) + \sum_{j>i} [E_{ij}^{short} (r_{ij}, q_i, q_j) + E_{ij}^{Coul} (r_{ij}, q_i, q_j)] + \\
&& E^{polar} (q_i, r_{ij}) + E^{vdW} (r_{ij}) + E^{barr} (q_i) + E^{corr} (r_{ij}, \theta_{jik})] \\
\end{eqnarray*}                           
\end{document}
